What is light pollution?

Watch a three-minute video on the causes and effects of light pollution, and discover ways to preserve dark skies.

Does it really matter?

YES! Light pollution wastes energy and money, disrupts global wildlife and ecological balance, has been linked to negative consequences in human health, and negatively affects astronomers and scientists. Read on to learn more about specific issues.

What can I do?

There is a WIN-WIN SOLUTION to light pollution! By changing outdoor lighting practices you can prevent light pollution while putting more light where you want it and using less electricity. Read on to find out how to make a positive difference.

Negative Effects of Light Pollution

A billboard exemplifying wasted light.
• COSTS: In the United States $10s of billions annually in electricity costs are wasted shining lights upward at night. These numbers do not include the costs of harvesting fossil fuels to generate electricity.

• ENERGY CONSUMPTION: Most of the energy required to power all of the wasted light comes from burning fossil fuels, contributing to other types of pollution.

• HEALTH: New studies point to dramatic health consequences from the disruption of the natural human day/night cycle. Unnatural light at night affects hormone production and reduces the strength of the immune system.

• THE ENVIRONMENT: Artificial light at night has been shown to disrupt the mating, migration, and hunting behaviors of many different species, and consequently the ecological community as a whole.

• LOSS OF NIGHTTIME SKY: The view of stars and dark night skies is rapidly being lost. Generations are growing up having never seen the Milky Way. Sky glow resulting from artificial lighting dramatically hinders the science of astronomy.

The Solution

We can reclaim vast amounts of energy currently wasted inadvertently into the night sky by poorly designed outdoor lighting. We can do this by using light fixtures that are shielded to reflect light down where it is needed, as well as using the smallest number of lights and lowest wattage bulbs necessary to effectively light an area.

The International Dark Sky Association has a list of distributors that sell approved fixtures to prevent light pollution.

• START WITH YOUR OWN HOME AND YARD: Lead by example in adopting good lighting practices. Put your own house in order first.

Good downward-pointing light fixtures.
• SPREAD THE WORD: The solution to light pollution is 90% education and public awareness, and 10% technology. Show examples of good lighting to your friends and neighbors. Once people see it in action, and understand its implications for cost savings and enhanced visibility, they are far more likely to adopt good lighting practices on their own.

• CREATE CHANGE IN YOUR LOCAL GOVERNMENT: One house doesn’t make much of a difference compared to an entire city and large retail complexes. The best way to make a significant difference is to help your local government create a new lighting ordinance that regulates lighting practices on a large scale. An excellent resource is the International Dark-sky Association.